Added a multi-stage Dockerfile for a lean production image and tweaked main.go for better app serving.

.github/workflows/ci.yaml

@@ -0,0 +1,88 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - main
+    paths-ignore:
+      - 'README.md'
+      - 'helm/**'
+
+jobs:
+
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: 1.22.5
+
+      - name: Build the application
+        run: go build -o app .
+
+      - name: Run tests
+        run: go test ./...
+
+  code-quality:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Run golangci-lint
+        uses: golangci/golangci-lint-action@v4
+        with:
+          version: latest
+
+  push:
+    runs-on: ubuntu-latest
+    needs: build
+
+    steps:
+      - name: checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Login to DockerHub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_TOKEN }}    
+
+      - name: Build and push Docker image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          files: ./Dockerfile
+          push: true
+          tags: ${{ secrets.DOCKER_USERNAME }}/go-web-app:${{github.run_id}}
+
+  update-newtag-in-helm-chart:
+    runs-on: ubuntu-latest
+    needs: push
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          token: ${{ secrets.TOKEN }}
+
+      - name: Update image tag in Helm chart
+        run: |
+          sed -i "s/tag: .*/tag: \"${{github.run_id}}\"/" helm/go-web-app-chart/values.yaml
+
+      - name: Commit and push changes
+        run: |
+          git config --global user.name "anirban banerjee"
+          git config --global user.email "anirban.banerjeeuv@gmail.com"
+          git add helm/go-web-app-chart/values.yaml
+          git commit -m "Update image tag to v${{github.run_id}} in Helm chart"
+          git push origin main

Dockerfile

@@ -0,0 +1,27 @@
+# *********** STAGE_1******************
+
+FROM golang:1.22.5 as BASE
+
+WORKDIR /app
+
+COPY go.mod .
+
+RUN go mod download  #for installing dependencies from the dev team
+
+COPY . .
+
+RUN go build -o main . 
+
+# ***********STAGE 2 ( with distroless-image) ******************
+
+FROM  gcr.io/distroless/base
+
+WORKDIR /app
+
+COPY --from=BASE  /app/main  .
+
+COPY  --from=BASE  /app/static  ./static
+
+EXPOSE 8080
+
+CMD ["./main"]

helm/go-web-app-chart/.helmignore

@@ -0,0 +1,23 @@
+# Patterns to ignore when building packages.
+# This supports shell glob matching, relative path matching, and
+# negation (prefixed with !). Only one pattern per line.
+.DS_Store
+# Common VCS dirs
+.git/
+.gitignore
+.bzr/
+.bzrignore
+.hg/
+.hgignore
+.svn/
+# Common backup files
+*.swp
+*.bak
+*.tmp
+*.orig
+*~
+# Various IDEs
+.project
+.idea/
+*.tmproj
+.vscode/

helm/go-web-app-chart/Chart.yaml

@@ -0,0 +1,24 @@
+apiVersion: v2
+name: go-web-app-chart
+description: A Helm chart for Kubernetes
+
+# A chart can be either an 'application' or a 'library' chart.
+#
+# Application charts are a collection of templates that can be packaged into versioned archives
+# to be deployed.
+#
+# Library charts provide useful utilities or functions for the chart developer. They're included as
+# a dependency of application charts to inject those utilities and functions into the rendering
+# pipeline. Library charts do not define any templates and therefore cannot be deployed.
+type: application
+
+# This is the chart version. This version number should be incremented each time you make changes
+# to the chart and its templates, including the app version.
+# Versions are expected to follow Semantic Versioning (https://semver.org/)
+version: 0.1.0
+
+# This is the version number of the application being deployed. This version number should be
+# incremented each time you make changes to the application. Versions are not expected to
+# follow Semantic Versioning. They should reflect the version the application is using.
+# It is recommended to use it with quotes.
+appVersion: "1.16.0"

helm/go-web-app-chart/templates/deployment.yaml

@@ -0,0 +1,26 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: go-web-app
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: go-web-app
+  template:
+    metadata:
+      labels:
+        app: go-web-app
+    spec:
+      containers:
+      - name: go-web-app-container
+        image: anirbanb13/go-web-app:{{ .Values.image.tag }}
+        ports:
+        - containerPort: 8080
+        resources:
+          requests:
+            memory: "64Mi"
+            cpu: "250m"
+          limits:
+            memory: "128Mi"
+            cpu: "500m"

helm/go-web-app-chart/templates/ingress.yaml

@@ -0,0 +1,19 @@
+apiVersion: networking.k8s.io/v1
+kind: Ingress
+metadata:
+  name: go-web-app-ingress
+  annotations:
+    nginx.ingress.kubernetes.io/rewrite-target: /
+spec:
+  ingressClassName: nginx   #for the ingress resource to be picked by nginx ingress controller
+  rules:
+  - host: go-web-app.local
+    http:
+      paths:
+      - path: /
+        pathType: Prefix
+        backend:
+          service:
+            name: go-web-app-service
+            port:
+              number: 8080

helm/go-web-app-chart/templates/service.yaml

@@ -0,0 +1,12 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: go-web-app-service
+spec:
+  selector:
+    app: go-web-app
+  ports:
+  - port: 8080
+    targetPort: 8080
+    protocol: TCP
+  type: NodePort

helm/go-web-app-chart/values.yaml

@@ -0,0 +1,161 @@
+# Default values for go-web-app-chart.
+# This is a YAML-formatted file.
+# Declare variables to be passed into your templates.
+
+# This will set the replicaset count more information can be found here: https://kubernetes.io/docs/concepts/workloads/controllers/replicaset/
+replicaCount: 1
+
+# This sets the container image more information can be found here: https://kubernetes.io/docs/concepts/containers/images/
+image:
+  repository: anirbanb13/go-web-app
+  # This sets the pull policy for images.
+  pullPolicy: IfNotPresent
+  # Overrides the image tag whose default is the chart appVersion.
+  tag: "24684450734"
+
+# This is for the secrets for pulling an image from a private repository more information can be found here: https://kubernetes.io/docs/tasks/configure-pod-container/pull-image-private-registry/
+imagePullSecrets: []
+# This is to override the chart name.
+nameOverride: ""
+fullnameOverride: ""
+
+# This section builds out the service account more information can be found here: https://kubernetes.io/docs/concepts/security/service-accounts/
+serviceAccount:
+  # Specifies whether a service account should be created.
+  create: true
+  # Automatically mount a ServiceAccount's API credentials?
+  automount: true
+  # Annotations to add to the service account.
+  annotations: {}
+  # The name of the service account to use.
+  # If not set and create is true, a name is generated using the fullname template.
+  name: ""
+
+# This is for setting Kubernetes Annotations to a Pod.
+# For more information checkout: https://kubernetes.io/docs/concepts/overview/working-with-objects/annotations/
+podAnnotations: {}
+# This is for setting Kubernetes Labels to a Pod.
+# For more information checkout: https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/
+podLabels: {}
+
+podSecurityContext: {}
+  # fsGroup: 2000
+
+securityContext: {}
+  # capabilities:
+  #   drop:
+  #   - ALL
+  # readOnlyRootFilesystem: true
+  # runAsNonRoot: true
+  # runAsUser: 1000
+
+# This is for setting up a service more information can be found here: https://kubernetes.io/docs/concepts/services-networking/service/
+service:
+  # This sets the service type more information can be found here: https://kubernetes.io/docs/concepts/services-networking/service/#publishing-services-service-types
+  type: ClusterIP
+  # This sets the ports more information can be found here: https://kubernetes.io/docs/concepts/services-networking/service/#field-spec-ports
+  port: 80
+
+# This block is for setting up the ingress for more information can be found here: https://kubernetes.io/docs/concepts/services-networking/ingress/
+ingress:
+  enabled: false
+  className: ""
+  annotations: {}
+    # kubernetes.io/ingress.class: nginx
+    # kubernetes.io/tls-acme: "true"
+  hosts:
+    - host: chart-example.local
+      paths:
+        - path: /
+          pathType: ImplementationSpecific
+  tls: []
+    # - secretName: chart-example-tls
+    #   hosts:
+    #     - chart-example.local
+
+# -- Expose the service via gateway-api HTTPRoute
+# Requires Gateway API resources and suitable controller installed within the cluster
+# (see: https://gateway-api.sigs.k8s.io/guides/)
+httpRoute:
+  # HTTPRoute enabled.
+  enabled: false
+  # HTTPRoute annotations.
+  annotations: {}
+  # Which Gateways this Route is attached to.
+  parentRefs:
+  - name: gateway
+    sectionName: http
+    # namespace: default
+  # Hostnames matching HTTP header.
+  hostnames:
+  - chart-example.local
+  # List of rules and filters applied.
+  rules:
+  - matches:
+    - path:
+        type: PathPrefix
+        value: /headers
+  #   filters:
+  #   - type: RequestHeaderModifier
+  #     requestHeaderModifier:
+  #       set:
+  #       - name: My-Overwrite-Header
+  #         value: this-is-the-only-value
+  #       remove:
+  #       - User-Agent
+  # - matches:
+  #   - path:
+  #       type: PathPrefix
+  #       value: /echo
+  #     headers:
+  #     - name: version
+  #       value: v2
+
+resources: {}
+  # We usually recommend not to specify default resources and to leave this as a conscious
+  # choice for the user. This also increases chances charts run on environments with little
+  # resources, such as Minikube. If you do want to specify resources, uncomment the following
+  # lines, adjust them as necessary, and remove the curly braces after 'resources:'.
+  # limits:
+  #   cpu: 100m
+  #   memory: 128Mi
+  # requests:
+  #   cpu: 100m
+  #   memory: 128Mi
+
+# This is to setup the liveness and readiness probes more information can be found here: https://kubernetes.io/docs/tasks/configure-pod-container/configure-liveness-readiness-startup-probes/
+livenessProbe:
+  httpGet:
+    path: /
+    port: http
+readinessProbe:
+  httpGet:
+    path: /
+    port: http
+
+# This section is for setting up autoscaling more information can be found here: https://kubernetes.io/docs/concepts/workloads/autoscaling/
+autoscaling:
+  enabled: false
+  minReplicas: 1
+  maxReplicas: 100
+  targetCPUUtilizationPercentage: 80
+  # targetMemoryUtilizationPercentage: 80
+
+# Additional volumes on the output Deployment definition.
+volumes: []
+  # - name: foo
+  #   secret:
+  #     secretName: mysecret
+  #     optional: false
+
+# Additional volumeMounts on the output Deployment definition.
+volumeMounts: []
+  # - name: foo
+  #   mountPath: "/etc/foo"
+  #   readOnly: true
+
+nodeSelector: {}
+
+tolerations: []
+
+affinity: {}